code: def test_accum_bounds():
      assert limit_seq((-1) ** n, n) == AccumulationBounds(-1, 1)
      assert limit_seq(cos(pi * n), n) == AccumulationBounds(-1, 1)
      assert limit_seq(sin(pi * n / 2) ** 2, n) == AccumulationBounds(
          0, 1
      )
      assert limit_seq(
          2 * (-3) ** n / (n + 3**n), n
      ) == AccumulationBounds(-2, 2)
      assert limit_seq(
          3 * n / (n + 1) + 2 * (-1) ** n, n
      ) == AccumulationBounds(1, 5)
  
imports: from sympy.concrete.summations import Sum
  from sympy.core.add import Add
  from sympy.core.numbers import I, Rational, oo, pi
  from sympy.core.singleton import S
  from sympy.core.symbol import Symbol, symbols
  from sympy.functions.combinatorial.factorials import binomial, factorial, subfactorial
  from sympy.functions.combinatorial.numbers import fibonacci, harmonic
  from sympy.functions.elementary.exponential import exp, log
  from sympy.functions.elementary.miscellaneous import sqrt
  from sympy.functions.elementary.trigonometric import cos, sin
  from sympy.functions.special.gamma_functions import gamma
  from sympy.series.limitseq import limit_seq
  from sympy.series.limitseq import difference_delta
  from sympy.testing.pytest import raises, XFAIL
  from sympy.calculus.accumulationbounds import AccumulationBounds
label_desc: Use image node_id 7 for calling a global function with example usage: test_accum_bounds() without return types